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“Most promising signs yet” of alien life on a planet beyond our Solar System

(www.skyatnightmagazine.com)
417 points fuidani | 17 comments | 17 Apr 25 08:02 UTC | HN request time: 0.847s | source | bottom
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seanhunter ◴[17 Apr 25 08:59 UTC] No.43714467[source]▶
Firstly that is completely badass science. The idea that you can use observations to detect the chemical composition of an exoplanet millions of kilometres away is an absolute triumph of the work of thousands of people over hundreds of years. Really amazing and deeply humbling to me.

Secondly, my prior was always that life existed outside of earth. It just seems so unlikely that we are somehow that special. If life developed here I always felt it overwhelmingly likely that it developed elsewhere too given how incredibly unfathomably vast the universe is.

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ta8645 ◴[17 Apr 25 09:20 UTC] No.43714565[source]▶
If life is very common in the universe, then that is probably bad news for us. It means that civilizations should exist that are millions of years more technologically advanced than us; and should be leaving telltale signatures across the sky that we'd likely have detected by now. And the absence of those signs would be relatively strong evidence that life, while common, isn't long-lived. Suggesting that our demise too, will come before too long.

If, on the other hand, life is relatively rare, or we're the sole example, our future can't be statistically estimated that way.

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Andrew_nenakhov ◴[17 Apr 25 09:36 UTC] No.43714650[source]▶
It is quite plausible that life is abundant, but sentience is not. If we take Earth, it formed 4.5 billions years ago, conditions became suitable to support life like 4B years ago and first known signs of life are dated 3.7B years ago.

Now, in just .5B years Earth would likely become uninhabitable due to Sun becoming a red giant. In other words, on Earth life spent 90% of its total available time before sentience emerged. So on one side life is constrained simply by time, and on the other, sentience might not be necessary for organisms to thrive: crocodiles are doing just fine without one for hundreds of millions of years. To think of it, it is only needed for those who can't adapt to the environment without it, so humans really might be very special, indeed.

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energy123 ◴[17 Apr 25 10:50 UTC] No.43715071[source]▶
This is now much less plausible. Intelligence, like eyesight, is believed to be a result of convergent evolution[0].

[0] https://www.quantamagazine.org/intelligence-evolved-at-least...

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lupusreal ◴[17 Apr 25 10:58 UTC] No.43715113[source]▶
Being intelligent doesn't necessarily lead to runaway technological development. Dolphins are smart but they're never going to invent radios to broadcast their existence to other star systems. They're stuck in the water and don't have thumbs. And even orangutans, who have thumbs and live on land, don't seem tracked for technology even if humans weren't around; their ecological niche is small even if we assumed humans weren't wrecking their environment, and they seem comfortable and steady in it.
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1. lordnacho ◴[17 Apr 25 11:18 UTC] No.43715215[source]▶
We don't even need to look at other species.

Humans have been just as smart as you and me, maybe even smarter according to cranial measurements, without inventing anything that significantly changed their way of life.

There could be loads of planets with prehistoric humans, having a fine time hunting with bows and picking fruit.

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2. Loughla ◴[17 Apr 25 13:40 UTC] No.43716673[source]▶
I don't think so, though. I think that unless there are limiting factors (no ores or some other necessary component) life would tend toward technology.

Curiosity as an evolutionary trait is quite an advantage, and I would think is necessary for intelligent omnivores. It's what helped us figure out what we could and couldn't eat, and taught us better techniques for living. Curiosity naturally leads to technological developments, I would argue.

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3. andrewflnr ◴[17 Apr 25 14:32 UTC] No.43717431[source]▶
> life would tend toward technology

Based on what evidence? We only know if it happening once, after a very long delay.

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4. npc_anon ◴[17 Apr 25 14:47 UTC] No.43717695[source]▶
All humanoids except our species are extinct, and it's not because we killed them.
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5. stnmtn ◴[17 Apr 25 14:58 UTC] No.43717882[source]▶
We really are pretty lucky that the industrial revolution happened. Thank god for England running out of trees to heat homes with, and abundant surface coal on that island.
6. Scarblac ◴[17 Apr 25 16:04 UTC] No.43718764{3}[source]▶
It's not? Didn't most of them coexist with us until they didn't?
7. griffzhowl ◴[17 Apr 25 16:17 UTC] No.43718959[source]▶
I think by the time we get to modern humans it would only be a matter of time for technology to develop to something like the current stage. The main evidence I can think of is the independent development of agriculture in about 4-5 regions, and the independent development of large complex civilizations in the Americas and Eurasia.

Humans are cultural learners, so this allowed cumulative cultural evolution from at least as far back as the transition from Olowan to Acheulean stone technologies with Homo erectus ~2-3 million years ago. By the time we get to Homo sapiens and Neanderthal this capacity for cultural learning seems much increased. Some paleoarchaeologists (e.g. Dietrich Stout) argue that technological development has been exponential as far back as H. erectus, just that the early stages of the exponential curve look flat for a long time.

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8. lordnacho ◴[17 Apr 25 19:36 UTC] No.43721179[source]▶
I think it only takes a small tweak for everything to stall.

Suppose say, that people only trust a small group. Extended family and lifelong friends, for instance. People get very violent as soon as they disagree on something, immediately wanting to settle disputes by force.

Nobody can strike a deal to do anything with anyone outside their group, and you certainly can't make agreements with a guy in Seattle to deliver things to London. You can't mine coal hoping to sell it to an as yet unknown person. There's no point in fishing more fish than you and your friends can eat.

What happens in this world? Well, I think people will still be intelligent. They'll still think about social situations, especially when it comes to mating. There will still be stories, and humor.

But we're not advancing tech, and we're not changing economically.

Why do I say it's a small tweak? Well, we've all met people who seem to not be able to work with anyone. It's not unlikely that out in the stars, there's some planet with people who have everything we have, but they can't get things to work.

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9. lupusreal ◴[17 Apr 25 20:09 UTC] No.43721637[source]▶
Humans only started planting grain about 12k years ago. Anatomically modern humans were gathering wild grain, but not planting grain, for about 100k years. Given this very long period of stagnation, I don't think humanities ascension was an inevitability.
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10. Loughla ◴[17 Apr 25 23:51 UTC] No.43723503{3}[source]▶
I think it's a natural product of curiosity. And I think that intelligent life would only be so because of curiosity.

You want to figure things out or you're interested in seeing what happens when you fuck around with things.

So I think a technological progression is a natural progression for intelligent life.

Does that make sense? I feel like I'm not explaining myself well.

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11. andrewflnr ◴[18 Apr 25 03:39 UTC] No.43724768{4}[source]▶
Lots of animals have been curious for hundreds of millions of years, but technology more advanced than breaking bits off rocks and sticks has only been around a couple thousand years. If you say it's a "natural progression", you also have to say there are serious barriers that most species will never pass.
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12. energy123 ◴[18 Apr 25 03:43 UTC] No.43724799{3}[source]▶
Mutation is random but selection is non-random. Multilevel selection could select against those scenarios you're talking about. Collaboration could be yet another thing that comes from convergent evolution.
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13. griffzhowl ◴[18 Apr 25 09:21 UTC] No.43726375{3}[source]▶
I know about the Natufan culture gathering and processing grain with grindstones from about 20k years ago, but don't remember anything from 100k years ago. Were they using grindstones to process grain? I'd have thought grass grains wouldn't be a good food source otherwise.

In any case, the seeming stagnation is part of what I meant by the early part of an exponential curve looking flat: broadly it might look like not much is happening, but there are small changes all the time.

Lack of evidence is also a problem when looking that far back: we have little concrete evidence of what these people were doing with wood, fibres, and other perishable materials.

Having said that, archaeologists used to talk about a "cultural revolution" that happened 20-30k years ago. (Maybe they still talk about it, I just haven't looked at the research recently). This was the period of the famous Lascaux cave paintings and what looks like an explosion of greater complexity in tool assemblages. So it's possible there was some rare cognitive leap at that time, or again it could be that we lack the evidence that would show the more gradual progression.

14. Loughla ◴[18 Apr 25 14:31 UTC] No.43728439{5}[source]▶
Okay?
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15. andrewflnr ◴[18 Apr 25 14:55 UTC] No.43728658{6}[source]▶
So the notion that "life would tend toward technology", charitably speaking, does not make any useful predictions. Based on all evidence available, including the dearth of extraterrestrial technosignatures, you can't rely on it happening in any particular situation or timeframe. At best it's speculation, more likely it's just false.
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16. fc417fc802 ◴[18 Apr 25 21:19 UTC] No.43731959{4}[source]▶
Random walks only progress if they don't get trapped in a local minima. GP example is but one entirely contrived scenario. The point is that technological development depends on many factors and it's entirely plausible that some of them aren't strongly selected for.

This seems to be supported if you consider how long it took for humans to emerge and the fact that other fairly intelligent species exist alongside us but didn't follow the same path. If you suppose that technological development has a clear selection path then why isn't there any evidence of space fairing dinosaurs?

17. Loughla ◴[18 Apr 25 22:12 UTC] No.43732284{7}[source]▶
Correct, we disagree in what we think.